METHOD FOR REMOVING RADIOACTIVE CONTAMINANTS Russian patent published in 1999 - IPC

FIELD: decontamination of metal surfaces from radionuclides in nuclear engineering. SUBSTANCE: metal surfaces contaminated with finely dispersed particles of irradiated nuclear fuel formed during mechanical splicing (cutting) of fuel elements are decontaminated by their treatment with sulfamic acid solution doped with sodium fluoride; first they are treated with solution containing 30 to 90 g/l of nitric acid, 3 to 5 g/l of sulfamic acid, and 2 to 4 g/l of sodium fluoride at 90-95 C, then with solution containing 30 to 50 g/l of hydrogen peroxide, 30 to 50 g/l of oxyethylidenedandyphosphonic acid, and 30 to 50 g/l of sodium hydroxide. This process ensures approximately 400 times more effective decontamination of metal surfaces. EFFECT: improved decontamination efficiency. 4 cl, 1 tbl